Project Summary The proposed Career Development Award will provide the Candidate, Amy T. Makley, MD, with the means to attain independence as a scientific investigator. Dr. Makley?s ultimate research goals are to become an independent surgeon scientist investigating the downstream effects of resuscitation with stored blood products following hemorrhagic shock. The research project proposed in this application focuses on the immense clinical problem of morbidity and mortality following traumatic injury. Specifically, up to 50% of deaths from hemorrhage are potentially preventable. While the mainstay of treatment of hemorrhage includes transfusion of stored blood components, knowledge remains limited regarding the effects of stored blood transfusion on the development of complications including acute lung injury. This study aims to investigate the effects of resuscitation with stored blood, ultimately targeting the breakdown of the pulmonary endothelial barrier and development of acute lung injury after hemorrhage. Sphingosine-1-phosphate (S1P) and its primary endothelial receptor, sphingosine- 1-phosphate receptor subtype-1 (S1PR1) have integral roles in the preservation of the endothelial barrier, and preliminary data supports a disruption of S1P homeostasis after exposure to stored blood. The experimental design proposed in this application will elucidate the mechanisms by which S1P and its receptor are affected following exposure to stored blood, using both an in vivo model of traumatic injury and hemorrhagic shock in mice as well as an in vitro model of pulmonary- specific human and murine endothelial cell monolayers. The Career Development Plan outlined in this proposal includes a robust mentorship team led by Dr. Timothy Pritts and Dr. Alex Lentsch, as well as a formal Scholarship Oversight Committee (SOC) including Drs. Michael Edwards, Charles Caldwell, and Erich Gulbins. An in- depth program of additional training in molecular biology under the tutelage of the SOC is proposed to augment Dr. Makley?s experiences and aid in her development. In addition, a reduction in her clinical and educational administrative responsibilities is proposed to provide her with 75% protected research time. She has access to outstanding research facilities and equipment to complete all of the proposed experiments in this application. Dr. Makley has the complete and unwavering support of her Chair, Division, and Department of Surgery at the University of Cincinnati to succeed in her endeavor to become an independent scientist.